Frustrated by Magento? Then you’ll love Commerce Bug, the must have debugging extension for anyone using Magento. Whether you’re just starting out or you’re a seasoned pro, Commerce Bug will save you and your team hours everyday. Grab a copy and start working with Magento instead of against it.

Updated for Magento 2! No Frills Magento Layout is the only Magento
front end book you'll ever need. Get your copy
today!

Given the date on the Stack Overflow post that saved me this is probably old hat for most of you, but it looks like the MySQL configuration provided by Ubuntu 18’s default apt-get repositories defaults to using “the auth_socket plugin”, which links your MySQL logins with your actual system login. Gave me a bit of the get off my lawn once I figured out what was going on.